David A. Weitz

David A. Weitz (born October 3, 1951) is a Canadian/American physicist and Mallinckrodt Professor of Physics & Applied Physics and professor of Systems Biology at Harvard University. He is the co-director of the BASF Advanced Research Initiative at Harvard, co-director of the Harvard Kavli Institute for Bionano Science & Technology, and director of the Harvard Materials Research Science & Engineering Center. He is best known for his work in the areas of diffusing-wave spectroscopy, microrheology, microfluidics, rheology, fluid mechanics, interface and colloid science, colloid chemistry, biophysics, complex fluids, soft condensed matter physics, phase transitions, the study of glass and amorphous solids, liquid crystals, self-assembly, surface-enhanced light scattering, and diffusion-limited aggregation. More recently, his laboratory has developed Force spectrum microscopy, which is capable of measuring random intracellular forces. As of July 2013, he has a Hirsch index of 173.

Weitz received his B.Sc. in Physics from the University of Waterloo and his PhD in superconductivity from Harvard. He then worked as a research physicist at Exxon Research and Engineering for nearly 18 years, leading the Interfaces and Inhomogeneous Materials Group and Complex Fluids Area. He then became a Professor of Physics at the University of Pennsylvania, before moving to Harvard in 1999.